Pa Mineral Rights laws

We have property in Wyoming County, Pa, since 1976. We recently gound out that the mineral rights have been severed from the surface when exploring a gas lease. The person with the mineral rights has since passed away. How do we go about petioning for these mineral rights on the property that we own?

I have heard of people trying to quiet the title through court petition, but I personally would not accept it as good title to the mineral rights.

The only 100% for sure way to get it (in my eyes at least) is to find the heirs and buy it from them.

Thank you for your advice.